Fingerprint sensors are sometimes used as “navigation tools”, for example to move a cursor or pointer on a display or to perform selections of items presented on a display etc.
To be able to use a fingerprint sensor for such a navigation tool application, it is necessary to somehow track movement of the finger of a user across the fingerprint sensor.
According to one approach, described in U.S. Pat. No. 6,408,087, successive fingerprint images are captured at a frame rate of 1000 frames per second, and the displacement of fingerprint ridges and pores is determined based on a comparison of the successive fingerprint images.
Although the use of a capacitive fingerprint sensor for controlling a pointer as described in U.S. Pat. No. 6,408,087 has several benefits as compared to conventional pointing devices, there still appears to be room for improvement.